Drug interactions
Lapatinib + Mirtazapine
Severity: Moderate
Lapatinib and Mirtazapine: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Lapatinib prolongs the QT interval in a dose-related way and mirtazapine can contribute a smaller effect. Combined use may raise the risk of torsades de pointes, especially with electrolyte disturbances.
What this interaction means in plain words
Lapatinib and Mirtazapine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Lapatinib belongs to Oncology; Mirtazapine belongs to Central Nervous System.
Why it happens
Additive QT prolongation.
What to do
Obtain a baseline ECG and correct potassium and magnesium before starting lapatinib, then monitor the ECG periodically. Consider an alternative antidepressant if the QTc becomes prolonged.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Lapatinib and Mirtazapine, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 14 days on the web. No card needed.
Other interactions of Mirtazapine
- Isocarboxazid + Mirtazapine Contraindicated
- Mirtazapine + Phenelzine Contraindicated
- Mirtazapine + Pimozide Contraindicated
- Mirtazapine + Procarbazine Contraindicated
- Mirtazapine + Rasagiline Contraindicated
- Mirtazapine + Selegiline Contraindicated
Other interactions of Lapatinib
- Dofetilide + Lapatinib Contraindicated
- Ibutilide + Lapatinib Contraindicated
- Lapatinib + Pimozide Contraindicated
- Lapatinib + Saquinavir Contraindicated
- Lapatinib + Thioridazine Contraindicated
- Adagrasib + Lapatinib Major
Frequently asked questions
Can I take Lapatinib with Mirtazapine?
MediHelp rates the interaction as moderate. Lapatinib and Mirtazapine can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Lapatinib prolongs the QT interval in a dose-related way and mirtazapine can contribute a smaller effect. Combined use may raise the risk of torsades de pointes, especially with electrolyte disturbances.
How serious is the interaction between Lapatinib and Mirtazapine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Obtain a baseline ECG and correct potassium and magnesium before starting lapatinib, then monitor the ECG periodically. Consider an alternative antidepressant if the QTc becomes prolonged.
What other medicines interact with Mirtazapine?
MediHelp also lists interactions of Mirtazapine with, for example, Isocarboxazid, Phenelzine, Pimozide. The full list is on the Mirtazapine page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
